Traditionally, a release binding is mounted on a ski directly in contact with the top surface of the ski. The evolution of ski manufacturing technology has resulted in skis, especially slalom skis, which are narrower in the "skate" area than before. The skate area serves to support a ski boot. The boot projects laterally to either side of the ski, which, on a steep slope, as a result of the contact between the boot and the snow prior to the corresponding edge of the ski, digs into the snow. This causes the ski to shift and possibly result in imbalance, causing the skier to fall.
To overcome this disadvantage, it has been suggested to raise the boot relative to the ski by interposing a plate between the ski and the boot, with the binding, toe piece, and heel piece being mounted on said plate. Apart from the fact that it increases the weight of the ski-binding assembly, this plate has the disadvantage of clamping the ski over the length of its contact with the ski. It is desirable for a ski to deform as freely as possible when it is used, to provide the best performance.
Another solution consists in equipping a ski with two independent blocks, each mounted on the top surface of the ski and serving to mount the toe piece and heel piece of the binding. This does not provide clamping action over the length of the binding area, as in the previous case. However, the distance of the toe piece and the heel piece from the surface of the ski is greater than that which is obtained with direct mounting on the ski. As well, there is an increase in the pressure of the boot on the binding which produces an increase in the tilting force of the binding. This tilting force translates to an increase in the camber or flexing of the ski which changes the behavior of the ski.